What is the power supply and communication for electric compressors?
HV/PHEV and EV vehicles have two batteries.
(※Quantity, capacity, etc. may differ depending on the vehicle)
- HV battery: Vehicle motor drive battery
- 12V battery: Battery for low voltage equipment
Electric compressors operate by receiving power from each battery.
The main classification is
- Control circuit drive power supply, communication system = LV battery
- IGBT drive circuit = HV battery
What is the inverter circuit electronic circuit block?
| Inverter circuit block | Function/Role | |
| ① | Power circuit | A circuit that supplies the voltage necessary for the operation of each electronic component and circuit such as the |
| ② | 12V detection circuit | Circuit that monitors the voltage of |
| ③ | Communication circuit | A circuit that allows communication between the vehicle and the inverter ( microcomputer ). Receives signals from the vehicle and sends compressor information to the vehicle. |
| ④ | Microcontroller ( +peripheral circuit ) | The so-called brain in humans. Exchanges information with the vehicle, obtains information on the inverter circuit, receives this information, generates appropriate motor control signals, performs protection, etc. |
| ⑤ | Sensor circuit | A circuit that detects the current flowing through the inverter, monitors the Li-ion battery (HV battery), and detects the temperature of parts. |
| ⑥ | Motor drive circuit | This circuit has a 3-phase (U, V, W) upper and lower (6 circuits used) circuit configuration that receives control signals from a microcomputer, performs switching operations for power devices, and drives a motor. |
| ⑦ | Filter/smoothing circuit | A circuit that reduces voltage fluctuations |
What is the communication circuit inside the inverter circuit electronic circuit block?
Purpose
The electric compressor communicates information with the vehicle using CAN or LIN communication.
What are the types of communication circuits?
CAN
Controller Area Network (CAN) is an internationally standardized serial communication protocol by ISO .
Up until now, the automobile industry has developed various electronic control systems for automobiles in pursuit of safety, comfort, low pollution, and low cost. These control systems are often configured with multiple bus lines for each system, resulting in an increase in wiring harnesses, resulting in increased weight and cost. Therefore, with the aim of “reducing wire harnesses” and “communicating large amounts of data at high speed via multiple LANs,” German electrical equipment manufacturer BOSCH developed CAN as a communication protocol for automobile electronic control systems. Developed.
LIN
LIN is an abbreviation for Local Interconnect Network , and it is a communication standard established by the LIN consortium, which mainly consists of European automobile manufacturers and semiconductor manufacturers, with the aim of reducing the cost of in-vehicle networks.
The LIN specification has been repeatedly revised, and three types , LIN Revision 1.3 , 2.0 , and 2.1 , are mainly used for automotive ECUs , but the last revision by the LIN Consortium was LIN Revision.2.2A .
It has now been transferred to ISO , and the LIN specification was published as ISO17987 in August 2016 . LIN is positioned as a sub-bus of CAN , making it possible to construct a network at a lower cost than CAN.
